I started the whole campaign again a few days ago, so it's not an older save. The problem appeared at the second starting of the mission (after Blacfoot Down). I'm not using mods. If I remember correctly, I didn't loot anything through the last mission, and my last actions were blowing up the wreckage and walking back towards Maxwell (so it was completely normal until Maxwell's loading image).
Please, tell me if I can help with any other details.